1. Field of Disclosure
The present disclosure relates to a linear delta mechanism. More particularly, the present disclosure relates to a stable linear delta mechanism and a delta robot with the foregoing delta mechanism.
2. Description of Related Art
A conventional serial-linked robot mechanism requires a serial-linked three-axis adjusting mechanism. This adjusting mechanism can automatically adjust the horizontal and vertical posture and angle of a movable platform in the adjusting mechanism. This adjusting mechanism, however, has drawbacks as follows:
(1) The serial-linked mechanism is apt to cause error accumulation;
(2) The serial-linked mechanism having a long load flow line, which makes the mechanical strength weaker and easily deformed;
(3) The inertia has to be increased in improving the strength of a serial-linked mechanism, which results in more difficult mechanism control, lower accuracy and worse energy loss; and
(4) The serial-linked mechanism is not able to effectively eliminate the thermal deformation in operation.
To address the foregoing problems, the serial-linked mechanism in the industry is replaced with a parallel-linked mechanism, such as a delta mechanism. The delta mechanism is a closed-loop system. Robots adopting the conventional delta mechanism dispose three fixing stands surrounding a working platform, and extend three guide sets from the three fixing stands. One end of each of the guide sets consists of a linear actuator, the other end of each of the guide sets consists of a linkage rod set connected to a movable platform. These linear actuators respectively move forth and back along single direction, to drive the movable platform moving in a three-dimensional space. This type of conventional parallel-linked mechanism can resolve issues such as complicated structure, large inertia, and large load.
The conventional parallel-linked mechanism mentioned above can resolve part of the problems of serial-linked mechanism, but has drawbacks listed as below:
First, three actuating sets surrounding a working platform are disposed around the parallel-linked mechanism. As a result, the space above and around the working platform cannot be used efficiently. The space below the working platform for transmitting work piece is also greatly limited, because of the three actuating sets and their fixing structures taking part of the space.
Second, since the space below the working platform is used during working process, the working height of the working platform cannot be lowered.
Third, the three actuating sets and their fixing structures are disposed surrounding the working platform. The total space taken can be huge and inconvenient for installing and transporting.
Fourth, the three actuating sets scattering surrounding the working platform spread the working inertia and is not easy to be controlled. Therefore, it is more difficult to tune the stability of the conventional linear parallel-linked robot.